This application relates to an air machine with an air-driven turbine drives an air compressor, wherein a thrust bearing surface is provided with a cooling air path, and a portion of the cooling air is tapped to drive air within a hollow cavity.
Air machines are known and include a turbine driving a compressor. Partially compressed air is delivered to the compressor, and the compressor is driven to further compress this air. This compressed air is passed downstream to drive a turbine, with the turbine in turn driving the compressor as the air expands across the turbine. This expanded air is then utilized for a downstream use, such as cabin air for an aircraft.
The known air machines have a shaft which connects the compressor and the turbine.
A thrust bearing surface is provided by a member which is fixed to rotate with the shaft of the air machine. The thrust bearing surface faces a housing surface, which has a hollow chamber on an opposed side of a housing wall. The air sitting within the hollow chamber becomes stagnant, and adds heat to the housing and thrust bearing interface.